Mesosiderite, group A2
standby for clover springs photo
Found 1954
34° 27' N., 111° 22' W.

A single large mass weighing 7.7 kg was found by a rancher named Jim Wingfield about 13 miles SW of Clover Springs in Gila County, Arizona. While setting out salt licks for his cattle, Jim picked up an odd looking rock that he considered to be "worth investigating"; it was ultimately determined to be a rare mesosiderite. The meteorite was subsequently acquired by Harvey Nininger, who eventually sold the main mass to the British Museum of Natural History.

Clover Springs is a moderately metamorphosed mesosiderite composed of a uniform FeNi-metal matrix with broken silicate clasts dispersed throughout. Mineral clasts include Ca-poor pyroxene, plagioclase, and olivine, the latter considered likely to be of xenolithic origin (Hassanzadeh et al., 1990). Lithic clasts are predominantly plagioclase-rich cumulate eucrite fragments. As with all mesosiderites, Clover Springs has experienced low levels of shock with features indicative of shock stage S1/S2. In the classification scheme of Floran (1978) and Hewins (1984), Clover Springs was assigned to metamorphic group A2 (see the Bondoc page for further information about this classification scheme).

The specimen of Clover Springs shown above is a 1.35 g partial slice with a fusion-crusted edge. The photo below is an excellent petrographic thin section micrograph shown courtesy of Peter Marmet.

standby for clover springs ts photo
click on image for a magnified view
Photo courtesy of Peter Marmet